In current business environment, enterprise data is often moved from virtually any source location into data warehouses or databases so that the changed data can be used to facilitate business practices. This task can create an enormous overhead on the existing resources if an entire volume of data is migrated from the source to the target whenever the source is updated. Change data capture (CDC) is an approach designed to accomplish data migration and data integration efficiently. CDC comprises of tasks to detect, extract, transfer and apply data modification changes. Transactional changes are captured from operational systems and applied to one or more data repository systems. CDC can be implemented in both source and target systems. When CDC is implemented in the source system, it is offered as a feature of the source system, where the source systems use triggers, logs files and other methods to identify the data that has changed since the last extraction. The change data is made available to target systems in a controlled manner.
When CDC is implemented in the target systems, the source system is relieved of providing any CDC service. Reducing the amount of data traffic between source and target databases, while reducing or eliminating the need to for modifications to the schema of the source database may be desirable.